sundialsvc4 does this frequently actually. A recent example Re^4: Examples where XML::Simple is the optimal choice? (ignoring the obvious pointed out here). This has been going on for years and they've never bothered to use their 'skills' to help diagnose the problem, despite various 'call to arms' posts over this period that we should all band together to improve this site/community/perl. The phrase you use 'obvious troll replies' is interesting, there's obvious abuse, for example name calling, then there's subtle trolling (which is arguably a form of abuse), for example posting the same hackneyed incorrect advice time and time again for years despite having been corrected many times already. The former is unpleasant the latter is down right dangerous. Neither are ideally what we want here.

tye has many interesting write ups on the subject of trolls. IMHO he has vast experience of the issue here (this site), and likely elsewhere. In the history of this site we've had some very disruptive trolls, some even damaging to the stability of the site. These posts are worth searching for, over the years tye has spoken on the subject many times, with great insight of the issues at hand.

The perceived hostility likely comes from the fact that the usual tactics have often failed to yield positive results. For example, posting a correction, pointing out the he is wrong. The majority of such posts don't even get a reply. There's a good chance that you'll see exactly the same thing posted again later.

Sticking to the facts and pointing out the errors/problems with sundialsvc4 posts seems to have zero impact on him, however we can only hope the uninitiated see such corrections and learn from them. In this respect, and matching our (yours and my) expectations of being called out/corrected when wrong is a good gauge of the site. We should not be afraid to correct one another, even if the person being called out never improves. It's far easier to change your own behaviour than it is to alter someone else's, but this is an ongoing struggle and I can appreciate that people may grow tired, bored or frustrated with the root cause of the problem and lash out.

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